SUMMARY ? CORE 3 The Neurobiology and Genetics Laboratory Core (NGLC) will carry out specialized assays for multiple projects and thereby insure optimal and comparable reliability across projects. It offers an economy of scale and moves resources as study priorities change. The assays fall into several major domains. Toxicology assays such as ones using brain tissue provide a longer time frame on most recent exposure to psychotropic drugs than body fluids since brain levels tend to be 10-40 times higher. This will be valuable for the postmortem brain studies in Project 1 where drugs may alter the results. The second domain is genetics and epigenetics. Here assays will include gene variants, methylation and gene expression assays. The latter domain is applicable to Projects 1, 2 and 5. The core will assay salivary amylase and cortisol in Project 5 and the responses will also be correlated with findings from Projects 3 and 4. The core will prepare DNA and RNA for assay by the New York Genome Center checking integrity of the DNA and RNA and preparing samples with the correct concentration for assay. Other assays for P5 include BDNF, PUFAs, Tryptophan, Kynurenine, Quinolinic acid, Neopterin, and preparing samples for cytokine assays and assaying cytokines from TSST samples (IL-6, TNF-alpha, C- reactive protein). Since Project 6 is looking at how suicidal behavior may be predicted by the large imaging data sets from Projects 3 and 4, it will also consider the impact of the laboratory data from Project 5. Thus, findings from this core are relevant directly or indirectly to every project